Electric welding-machine.



S. B. FIELD.

ELECTRIC WELDING MACHINE.

APPLICATION FILED MAR.20, 1914'.

Patented Feb. 9, 1915.

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ELECTRIC WELDING MACHINE.

APPLICATION FILED MAR.20, 1914 7 4 J. W 9m 1 M 7 I: 7 0a m 6Q s 2 w "v 0Q WI M QW/ d E 7 m m l M 9 w a I BL wdilbjacd S, B. FIELD.

ELECTRIC WELDING MACHINE.

APPLICATION FILED MAR. 20, 1914. .63)

Patefited Feb. 9, 1915.

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S. B. FIELD.

ELECTRIC WELDING MACHINE.

APPLICATION FILED MAR. 20, 1914.

Patented Feb. 9, 1915.

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S. B. FIELD.

ELECTRIC WELDING MACHINE.

APPLLOATION FILED MAR. 20, 1914.

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Patented Feb. 9, 1915.

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ELECTRIC WELDING MACHINE. I APPLICATION FILED MAR. 20, 1914'.

Patented Feb. 9, 1915.

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SAMUEL B. FIELD, OF HOLBROOK, MASSACHUSETTS, ASSIGNOR OE ONE-FOURTH T0PNEUMATIC SCALE CORPORATION, LIMITED, OF QUINCY, MASSACHUSETTS, A COR-PORATION OF MAINE, AND THREE-FOURTHS T0 WILLIAM H. DOBLE, OF QUINCY,

MASSACHUSETTS.

ELECTRIC WELDING-MACHINE.

Patented Feb. 9, 1 915.

Application filed March 20, 1914. Serial No. 826,000. v

To all whom it may concern:

lie it known that I, SAMUEL FIELD, citizen of the United States,residing at llolbrook, county of Norfolk, State of Massachusetts, haveinvented a certain new and useful Improvement in Electric \Velding-Machines, of which the following is a specification, reference being hadtherein to the accom ninying drawings.

In electric welding machines heretofore in use for welding together twoplates or bars of metal it has been customary to unite them by spotwelding, so-ealled, whereby the two parts are welded together in spotsat intervals apart from each other, this being done usually byinterposing .the two plates which are to be welded together between twopins or points which form electric terminals connected with atransformer in a circuit, and then by bringing these two terminals intocontact with the opposite faces of the two plates, said two plates beingin contact with each other so as to complete the circuit, the two platesare welded together at the spots in contact with the said terminals.After the two plates are united at one point in this manner the pins areseparated from contact with the plates, then the plates are moved alongto another position between the said pins which are again brought intocontact with the plates and the plates are then again united at suchsecond spot engaged by the pins. This process is continued, moving theplate about from one position to another until the requisite number ofpoints of union are accomplished. By this method, however, the weldingcan take place only at one spot at a time and the welding pins have tobe withdrawn from contact after each operation, and then the plates haveto be moved along and the pins brought. into contact again, thus makinga slow and laborious process.

One ob ect of the present invention is to' .spot, because the currenthas to be divided or split, going half to each spot. Under practicalconditions, however, owing to the fact that there is almost always moreor less lack of uniformity in the conductivity of a given plate, due toeither scale on the plate or difference in density or to otherconditions, it is found that the current will not split even, so that agreater amount of cur-. rent than is necessary goes to one spot andburns the plate and melts part of the point, while the other point doesnot receive sutlicient current to make a weld. For the above reasonsIhave found that more perfect results are obtained if it is attempted tomake the weld at only one spot at a. time with each transformer. Inorder, however, to carry the current to make the second spot I havefound that it is desirable to so arrange the contact, points that beforethe contact point which is making the weld entirely leaves contact withthe plate the next succeeding point should begin to make contact. It isnecessary that the second point shall begin to contact with the platebefore the first point fully leaves the plate in order to provide acontinuous outlet for the current and avoid drawing an are. It is alsofound that in spot welding there is a tendency of the plate to buckle atthe point of the weld and that it will buckle if the pressure isentirely removed before the plate has sufficiently cooled, as forinstance, if the contact point is withdrawn allat once, such forinstance as would take place if the contact point has a movement atright angles away from the plate. The effect of the buckling is to drawthe sheet that buckles away from the otherthat the gradual removal ofthe pressure by thisrotary action will hold the plates under sufficientpressure to prevent the buckling. That is, the portion of the contactpoint which still remains in contact with the plate will exertsufficient pressure to prevent the buckling under that portion fromwhich the point. has already Withdrawn from contact. As the contactpoint which has just made the weld begins to move away in the rotationof the roll the pressure from that particular contact "oint willdiminish.

One particular use for which my invention is especially adapted is thewelding together of the plates for forming hollow walls or panels formetallic boxes or shipping cases, especially of the folding variety,such for instance, as shown in application made by William H. Doble andSamuel B.

Field, Ser. No. 752,593, and for the purpose of more clearlyillustrating the construction flat-plates along one edge thereof, and iswelded to said two wall plates, said hinge plate being formed. withupwardly extending knuckle portions. It .is to be understood, however,that the invention is not limuted to use in the construction of boxpanels or in the welding of plates of the particular form shown anddescribed.

'I he invention will be understood .from the.

following description taken in connection with the accompanying drawingsand the novel features thereof will be pointed out and, clearly definedin the claims at the close of the specification.

In the drawings,Figure 1 is-a plan of a machine embodying the invention,the trans former and overhead parts being removed. Fig. 2 is a sideelevation of the machine shown in Fig. 1, as viewed from the lower sideof Fig. 1 and showing'the transformer and other overhead parts. Fig. 3is'a ver-,

tical section on line 3-3 of Fig. 1. Fig. 4 is a section on line -44 ofFig. 2. Fig. 5' is an enlarged view partly in section on line 5-5 ofFig. 2. \Fig. 6 is a development of the spot welding roll. Fig. 7 is aplan view partly broken .away of a grid with one of the flat plates andthe corrugated plate held by said'grid other ready to be passed throughthe welding machine for the purpose of spot welding. Fig. 8 is a sectionenlarged on line 88 of Fig. 7. Fig. 9 is an enlarged sectional viewpartly broken away of a certain in assembled relation to each portion ofthe driving mechanism of the machine. Fig. 10 is a plan view partlybroken away showing the second wall plate and the hinged plate inassembled relation to the corrugated plate and the said first wall plateafter the corrugated plate and first wall plate have been Weldedtogether and being now held in a jig preparatory to being passed throughthe second process of welding to unite the said second wall plate andthe hinge plate to the first wall plate and corrugated plate. Fig. 11 isa sectional view enlarged on line 11l1 of Fig. 10. Fig. 12

is a diagram showing the wiring for the spot welding. Fig. 13 is adiagram showing the wiring for the strip welding, that is, for thewelding in contlnuous lines, such as takes place to unite the hingeplate to the two wall plates. Fig. 14 is an end view enlarged of thelower right-hand corner of the jig shown in Fig. 10. Fig. 15 is an endview enlarged of the lower left-hand corner of Fig. 10. Fig. 16 is aleft-hand side View of the jig shown in Fig. 10. Fig. 17 is aperspective view showing one pair ofthe strip welding rolls and theirgrinding mechanism.

In order to give a better preliminary understanding of the purpose andconstruction, of the machine, especially the particular form of machineshown in the drawings as embodying the invention, the panel such ashereinbefore referred to and the method of assembling the several partswhich are to be welded together to form the panel will first bedescribed. This is particularly shown in Figs. 7,8, 10 and 11. The panelis composed of the two flat plates 1, 2 which may be termedrespectivelythe outer and inner plates, an interposed corrugated plate 3 which is socorrugated as to form a series of flat portions in parallel planesalternately engaging with the two flat plates 1', 2, and a hinge havinga box shank 4 and a series of eyes 5 to receive a hinge pin,'the entirehinge being formed integral, and saidbox shank portion' being ofa-thickness to just fit between the two flatplates 1, 2. These fourmembers, that is, the plates, 1, 2, the corrugated plate 3, and theshank of the hinge are all to be Welded together. This can beaccomplished by the machine of the present invention, as shown in thedrawings. First, the corrugated plate 3 and the inner plate 2 areassembled together, as shown in Figs.

. 7 and 8, and they are putthrough the spot welding portion ofthemachine, then the said two plates thus united together are taken outand they are assembled with the outer' plate 1 and the hinge portion, asshown 1n Figs. 10 and 11, andthey are then all put through both the spotwelding and the strip welding mechanisms of the machine to complete thewelding operation. j

. .The manner of assembling and holding together the plate 2 and thecorrugated.

plate 3 for the first operation is as follows:

A grid is provided consisting of a series of parallel slats 6 ofelectric conducting mathe slats so that there will be no lateralmovement of the corrugated plate. The slats (3 are preferably of copperor other suitab le material that has a low resistance as compared withthe metal plates which are to be welded together and form a goodelectrical contact with the flat portions of the corrugated plateresting thereon. The flat plate 2 is then laid on the top of thecorrugated plate, as shown in Figs. 7 and 8,

with alternate fiat portions of the corrugated plate in contact with theplate 2, and

the grid with the parts thus mounted are ready to be inserted into thewelding machine. v

The welding machine is provided with guides 2 10 on the carrier rollswhich engage the two opposite sides of the grid in its passage throughthe machine to prevent lateral displacement, of the grid. This operationwill in a manner hereinafter described weld the plate 2 to the flatportions of the corrugated plate 3 which are in contact with the plate 2at various spots, as indicated by the points 8, in Fig. 7. andcorrugated plate 3 are welded together, the grid will be removed fromthe machine and the united plates 2 and 3 will-be removed from the gridand bars 18 of good conducting material, preferably copper, for the samereason as described in relation to the slats 6 of the grid, will beinserted in alternate spaces in the corrugated plate. Then the plate 1and the hinge plates are all assembled in proper relation and placed ina jig shown in Figs. 10 and 11. When placed in the jig, the plate 2 andcorrugated plate 3 are turned the reverse side up from that shown inFigs. 7 and 8 so that the plate 1 will be on the upper side. The jigconsists of a four sided frame, as shown in Fig. 10, in the form of anopen square,

having the side and end strips 10, 11, 12 and 13. The space between the'two side strips 10, 11 is just sufficient to receive the assembledplates 1, 2, 3 and the hinge plate. Secured to the strip 9 which lapsonto strip 10 is a clip 14 which is formed with a recess in the inneredge of just sufiicient length and depth to receive one of the-eyes-5vof the hinge plate. Secured to the opposite side strip 11 is a clip 15which is adapted to engage between two eyes 5, 5 of the hinge platewhich is inserted into the edge of the panel on that side; thus thehinge plates are positioned against movement. The side and Afterthe'plate 2 end stripsare secured together between flat top and bottomplates in such manner as ,to leave a passage directly in alinement withthe eyes 5 of the hinge plate so that a lockingpin or red 16 may bepassed through said passage and through the eyes of the hinge plate onone side of the panel and a similar locking pin 17 may" be insertedthrough the eyes of the hingeplate on the opposite edge. At the cornersof the frame there are plates riveted to the side and end strips 10, 11,12 and 13 to firmly hold the frame together. Slidably mounted on each ofthe two end strips 12, 13 of the frame is a loop-shaped clip 20 having aportion on the under side of the frame which projects beneath the end ofthe plate 2 so as to form a support for the same. Secured to the endstrip 12 is a clip .22 which is adapted to reach over the upper edge ofthe plate 1, and secured to the side strip 11 at one end is a similarclip 22 which is also adapted to reach over the edge of the plate 1.These two clips 22, 22 are each formed with an elongated slot 23 whichis. engaged by a pin 24 secured to the strips to form guides for thesaid clips 22 so that they may be withdrawn, and the clips 20 both beingslidable 'on their respective strips may be,

moved endwise on their said strips so that the assembled plates 1, 2 and3,and the hinge plates may be inserted into the jig. Then the saidmovable slips are moved into the position shown in Fig. 10 and thelocking pins 16 and 17 are inserted.

Secured to the end strip 13 are the two clips 21 which project over thetop of the upper plate 1 so that as the clips 20 are engaged with theunder face of the plate 2 the overreaching top clips 21 and 22 serve tokeep the assembled plates 1, 2, and 3 fpom tilting on the supportingclips 20. The several clips and locking pins will hold the I assembledparts in fixed relation to each other. VVhen the parts are thusassembled, as shown in'Fig. 10, they are ready to be passed through thewelding machine a second time for the purpose of first welding togetherthe plate 1 and the corrugated plate 3, and at the same operation topass it along to a further stage in the machine where the hinge platewill be welded to both the plates 1 and 2. It is desirable that thehinge should be welded by a continuous line the entire length of thehinge plate near the edge thereof.

The mechanism for performing the welding operation will now bedescribed. The assembled parts which are to be welded together areintroduced at the left-hand end of the machine as viewed in Figs. 1, 2and 3, being passed over rotary idler rolls 30, thence they are grippedbetween the feed roll 31 and the presser roll 32, whence they are fedover the platen 33 where the upper plate is engaged by the projectingpoints 34 in the Welding roll 35 .wlrich produces the spot welding, aswill be hereinafter described, and after having'passed the spot machineif that is all the welding that is required, as in the case of unitingthe plate.

2 and the corrugated plate 3, but in the second passing through themachine after they have passed the welding roll'35 to weld the secondflat plate 1 to the corrugated plate 3 the assembled parts will bepassed along over the succession of carrier rolls 381, 382, thencebetween the upper strip welding rolls 39 and 39 and the lower stripwelding rolls 391, 391 which are sospaced apart as to engage the shanks4 of the hinge plates and produce a continuous line of welding until thejig with the assembled parts carried by the jig pass out onto .the rollswhence they can be taken ofi' at the rear end of the machine. The feedrolls 31 and 36 should be driven at the same surface speed as thesurfaizle speed of the shell 35 of the spot welding 1-0 7 The spotwelding roll consists of a cylindrical metallic shell 35 of goodconducting material, preferably copper, having in its periphery aplurality of contact points,

preferably nubs 34 of conducting material -which may be made integraltherewith if desired, but preferably made separable therefrom, as forinstance, being in the form of plugs or buttons inserted in theperiphery. For reasons to be hereinafter described the shell '35 ispreferably made in cylindrical sections insulated from each other. Thesenubs or buttons, as they will be termed for convenience, are preferablyof copper and are distributed throughout the area of the roll in suchmanner that as the roll turns, no two buttons in the same insulatedsection will at the same time contact with the surface which is beingwelded sufficient to make a welding contact, that is, each button aftermaking the contact will in the rotation of the roll continue slightly incontact, enough to support the roll and make the necessary pressure toprevent buckling and also to carry the current until the next succeedingbutton begins to contact withthe plate, but will move sufficiently outof con tact so that it willnot carry enough currentto make a weldingheat after the said next button makes suflicient contact to "carryenough current to make a weld. It is also preferable to arrange thesebuttons in staggered relation to each other. One reason for thestaggered relation isbecause 1f the spots are all welded in the sameline, as for the feed roll 36 they can be taken from the machine,projecting toward the front.

sheet or plate from the welding machine, it

It is therefore found best to has been found necessary to'so distributethe a points at which welds are made to avoid heatlng any one part ofthe plate greatly in excess of the balance of the plate, that'is, theweldlng points are so staggered on the roll that a weld being made hastime to cool off not only in itself, but the adjacent metal also hastime to cool before another weld is made close to this weld just made.

The metallic shell 35 is provided at its ends with short bushings 41 ofinsulating material, such for instance, as fiber, .and is mounted on ashaft 42 which is journaled inv bearings 43, 44 respectively carried bythe arms 45, 46 of a yoke fulcrumed on shaft 47.

The diameter of the shaft 42 is smaller. than the interior diameter ofthe shell 45 so. that there is an annular chamber 48 surrounding theshaft 42. The bushings 41'l1avea smaller interior diameter and greaterexterior diameter than the interior diameter of the chamber 48 andtheir'inner ends abut against a shoulder on the inner periphery of theshell. The shaft 42 has its end portions of reduced diameter and has ascrew threaded portion which receives the nuts 49 whereby the bush--ings 41 may be clamped firmly agai'nst'the shoulders in the shell 35.These bushings fit tightly on the shaft so that when the nuts 49 are setup tight the-shaft and shell will be made fast together and rotate asone.

The arms 45-, 46 of the fulcrumed yoke previously mentioned are rigidlytied together at their rear ends by a cross beam 50 secured to the saidarms, the said two arms 45, 46 and the cross beam 50 together formingthe yoke. Said yoke may be rocked or tilted on said fulcrum shaft 47.Vhen the' yoke is tipped up on its fulcrum it carries up the weldingroll 35 which is journaled in bearings carried by said yoke aspreviously described. The rigid connection of the several parts of theyoke with each other keeps the weldin roll and shaft parallel with theplaten. rod 51 is secured to the arm 46 of said yoke, as by beingmounted in brackets 52, 52 on the upper side of 1 the arm 46, andextends alongside of the weight 53is slidably mounted on said rod 51 andby adjusting said weight, the downwardpressure-ofthe welding roll uponthe work while upon the platenmay be regulated. A v

rod 54 looped around the weight rod 51 other.

-nut 57 on its upper end which form a stop to limit the downwardposition of the yoke and welding roll. This nut 57 may be ad- ]listed tovary the downward position of the yoke and welding roll, so as to adaptit to plates of different thicknesses which are to .be welded together.

The welding roll is preferably made in a plurality of cylindricalsections in alinement with each other and tied together but insulatedfrom each other, and the buttons 3% may if desired be disposed in thesame positionin each section, so that there shall be simultaneouselectrical contact with the plates which are to be welded together byone of the buttons on each section without electrical connection of onesection with the In the construction shown the drawings, the saidwelding roll is made in .two sections, see Figs. 1 and 1. The said twosections have their adjacent ends insulatedfrom each other by an annulardisk 58 of insulating material. There is also a collar 59 .of insulatingmaterial surrounding the shaft 42 made fast to the shaft and fittinginto a recess in the inner periphery of the roll 35, thus dividing thechamber 48 into two parts, said collar- 59 extending on both sides ofthe disk 58. The shaft 42 is formedwith a recess 60 in one side thereof,as shown in Fig. 4, which extends beyond both ends of the insulatingcollar 59 so that there is a communication between the two chambers 48through this recess 60. The shaft l2has port holes 61 and 610 drilledinto it from opposite ends for some distance and then opening out at oneside into the respective section of the chamber 48 with which that endof the shaft is connected. Connecting with the port 61 is a water pipe'62 through which cold water is introduced into the chambers 18 for thepurpose of keeping the roll from getting too hot and an outlet pipe 64leads from the port 610. The platen 33 which is preferably of copper isalso made in' two sections 69 with an insulating partition65'longitudinally between the two sections. It is mounted upon the frameof the machine with which it is firmly connected, as by bolts 67 andv isinsulated from the frame .of the'machine by insulat-' ing material 68surrounding the bolts and inserted between the platen and the supportingpart of the frame. v

Each section 69 of the platen is formed with a cross'partition 7 0, seeFig. 3, dividing each section into two chambers, said partitions 70 eachbeing formed with a-hole 71" passing through the same so as to afford awater port between the'two chambers of each section. Cold water'pipes 72lead into the two sections 69, each having a rubber pipe connection 73with the supply pipe 7 to insulate the platen from the metallic supplypipe and each section 69 is also provided with an outlet pipe'75 whichalso has an insulating section. The arrangement of the water pipes andports afford free circulation of water through the platen and thewelding rollwhich serve to keep them from getting too hot.

Each section of the welding roll and its corresponding section of theplaten are connected with a transformer having a primary coil and asecondary coil 81. One end of the secondary coil is provided with abrush .82 which engages with annular grooves 83 in the periphery of theroll 35. The other end of said secondary coil is connected to the platen3.

A rod 84 is secured by brackets 85 to the arm 45 ofthe yoke whichcarries the welding roll on the opposite side of the machine from therod 51 which is attached to the arm 46 of said yoke, said rod 81 beingpivotally connected by a rod 86 with a. lever 87 which is fulcrumed at88 to the beam 89 which forms a part of the frame of the machine. Saidlever 87 is adapted to be rocked onits fulcrum 88 by the rising andfalling of the said connecting rod 86 actuated by the rocking of saidyoke on its fulcrum, said yoke being tipped up by the passage of theplates which are to be welded together beneath the welding roll. Thesaid lever carries at its free end a contact member 90 which when itrises is adapted to make electric contact with a contact member 91 towhich is connected the wire 92 which leads to one of the poles of thegenerator, not shown. The contact members 90 and 91 are preferably ofcopper. Said contact 91 is attached to a metallic plate 93, preferablycopper, which forms a spring plate secured to a-post or standard 94which forms part of the frame and is insulated therefrom. Said springplate 93 forms a yielding support for the contact 91, its free endresting upon the upper side of an insulating stop 95 which prevents thecontact 91 from dropping below a certain point so that. the electricalcontact will not be tor from that to which the wire 92 is con-- nected.The parts are so adjusted that the lever 87 will not be raisedsufficiently to bring the contact 90 into contact with the contactmember 91, until the jig or grid, which carries the plates to be weldedhas entered between the welding rolls suificiently far to bring the saidplates into engagement with the contact points on the Welding roll. .Asthe plates to be Welded are passed under the welding roll, when one ofthe buttons in the Welding roll comes in contact with they upper platethe'yoke will be rocked suifimaking the recess 112 a chamber for thepur- 65 pose of allowing a current of water to flow ciently to causetherod 66 to lift the ,lever 87 and bring the contact member 90 intocontact with the contact member 91, thereby making the electricalconnection which produces the welding at the point where the buttonengages with the plate. When the welding roll has turned far enough tobring a new button into contact with the plate the circuit will be madethrough the said new button, and when the plates have passed ffrpmbeneath the welding roll the yoke will drop, and the circuit"will-bebroken.

One pole of each of the primary coils 80 is electrically connected withthe contact 90 and the other pole of each of the primary coils 80 iselectrically connected with the opposite pole of the generator from thatwhich is connected with the contact 91 so that the contact of the twocontacts 90 and 91 makes the electrical connection for both sections ofthe welding roll. The wiring is diagrammatically represented in Fig. 12.

The mechanism for the strip welding previously referred to and to whichthe plates are carried from the spot welding mechanism will now bedescribed: The strip welding rolls 39 are movable up and down while thestrip welding rolls 391 are mounted on a stationary axis. Each roll 39is mounted on a shaft 101 which is mounted in bearings carried by arocking yoke, each of said rocking yokes comprising two leverarms 102fulcrumed on shaft 103, and secured to the top of each pair of arms 102is a cross beam 104, thus making a rockingyoke somewhat similar in itsaction to the rocking yoke in which the spot welding roll 35 wasfulcrumed. There is a separate yoke for each of the two welding rolls39. The

shaft 103 is journaled in brackets 105 which form a part of the frame ofthe machine. (See Fig. 2). Each shaft 101 is journaled 1n bearings 106which are secured to a bracket 107, said bracket 107 being mounted ongibs 108 which form a part of the cross beam 104 of the yoke. The roll39 is in the form-of a ring secured to a collar 109 which serves as acarrier mounted fast on the shaft 101, said collar having a flange towhich the rol1'39 is secured by screw threaded pins 110 Which passthrough the rim of the wheel and into the flange of the collar 109. Thebearings 106 are provided with bushings 111. The

rolls or rings 39 can thus be easily mounted cess 112 in its innerperiphery which ifsclosed bya flange on the outer end of the' bearingand by said bushing 111 and by a flange collar or washer 113 which liesbetween. the collar' 109 and the bearing 106,

closing the space between the said collar 109 and the inner end of thebearing 106, thus therethrough to prevent the bearings from becoming toohighly heated. These chambers 112 aresupplied with inflowing waterthrough the pipes 114 and the water is discharged through the outletpipes 115. These pipes should have an insulating section of rubbersimilar to the insulating sections of the cold water pipes connectedwith the platen already described. The bearings 10.0 are insulated fromthe brackets with which they are connected, b insulating material 116.The brackets 10 are clamped to the gibs 108 by the bolts 117. Said shaft101 has ends of reduced diameter which are journaled in bearings 118which are secured to the under side of the lever arms 102 of the yoke. Arod 119 extends up from the frame of the machine through each of theyoke arms 102 and is provided with a nut 120 on the lower side of theyoke arm which forms a stop to limit the downward movement of the saidyoke, the said nut being adjustable so that the lowermost position ofthe yoke and therefore of the strip welding rolls 39 may be regulatedand adjusted. A spring 96 coiled around the rod 119 and bearlng againstthe upper side of said yoke arms 102 base plate 124 which is clamped ona gib 125 by a plate 126 and clamp screw 128. The gib 125 is fastened toa bracket 127. The bearing 123 is provided with a bushing 129 and isformed with an annular recess 130 which: is inclosed between the bearingand the bushing and a washer 131 to form a water chamber around thebearing, so as to prevent the bearing and the strip welding wheel 391from getting too highly heated. The said bushing 129and the bearing 123and the washer 131 are all solderedtogether to form one piece. hebearing 123 is insulated from the plate 124. Water is introduced intothe chamber 130 through a pipe 132 and is discharged through an outletpipe 133, the inlet pipe and theoutlet pipe each having an insulatingrubber section as already described with reference to the: other waterpipes. The end of the shaft 122 opposite to that on which the sleeve 123is mounted is journaled in a bearing 134 provided with an insulatingbushing 135.

A cylindrical box 136 of conducting Iraterial has its base seatedagainst the end of the sleeve 121 and has an annular notch in the outerperiphery of the base which is engaged by the side of the roll 391 whichprojects slightly beyond the end of the sleeve 121. This box 136 isrecessed and provided with a cover 137, thus forming a water chamberinto which cold water is introduced to cool the box 136 and thereby toprevent the roll 391 from becoming too highly heated. The water isintroduced through the pipe 138 and is discharged through an out; letpipe 139. A spring 140 under tension between the bracket 141 and thecover 137 presses the box 136 into ielding engagement with the side ofthe roll 391, so as to make electrical contact.

Each pair of strip welding rolls 39, '391 is connected with atransformer, each transformer. having a primary coil 150 and a secondarycoil 152. Each primary'coil 150 is mounted ona bracket 154. One end ofthe secondary coil 152 is connected with a tail piece 156 which is apart of the cylindrical box 136, thereby making electrical connectionwith the welding roll 391. The other end of the secondary coil 152 isconnected with a tail piece 157 which is electrically connected with theshaft 101.

The cross beam 104 of one of the-yokes is provided with an arm 160 towhich is pivotally connected one end of the rod 161, the other end ofsaid rod16l being pivotally connected with the lever 162 intermediatethe ends'of said lever 162, said lever 162 being fulcrumed at one end ona shaft 163 which is mounted in the frame 89, the free I end of saidlever 162 carrying a contact 'piece 164, preferably copper. A contactpiece 165, preferably of copper, isconnected with a wire 166 which leadsfrom one of the poles of the generator. WVhen the yoke consisting of thearm 102 and the cross beam 104 is turned up on its fulcrum as by thepassing of the plates which are to be welded between the welding rolls39,

. 391, the rod 161 will lift up the free end of the lever 162 andthereby bring the contact piece 164 into contact with the contact piece165, thus closing the circuit and causing thewelding action. The contact165 is mounted on a spring plate 167 which is mounted,

on the post 168. The free end of the spr ng plate 167 rests upon aninsulating block 169 to limit the downward movement of the contactmember 165, to prevent the contact with the contact member 164fromtaking;

place too soon. One wire of each of the primary coils 150 and 151 isconnected with one of the poles of the generator. The contact 164 isconnected with the other wire of the primary coils. The contact 165. iselectrically connected with the other pole of the generator, all asshown by diagram in Fig. 13. When the two contact members 164 and 165come into contact with each other, as above described, the circuit isclosed through both primary coils and both pairs of strip welding rollswill become operative.

The 'presser roll 32 is mounted on the shaft 130 which is jonrnaled inarms 181 fulcrumed on the shaft 182 and is held in yielding engagementwith the feed roll 31 by a spring 183. Mounted on the shaft 180 is apinion 184 which engages with a pinion 185 on the feed roll shaft 186.Said feed roll shaft 186 carries on its other end, opposite to thepinion 185, a bevel gear 187 which engages a bevel gear 188 on one endof a shaft 189, said shaft 180 carrying abevel gear190 which engageswith a bevel gear 191 on shaft 192 which carries the feed roll 36, sothatthe two feed rolls 31 and 36 yielding engagement on a shaft 206,said shaft 206 being jour naled in bearings 207 and carrying also abevel gear 208 which engages with the bevel gear 20.) on the spot.welding roll shaft 42, thus making driving connection between thedriving shaft 201 and the spot welding roll.

The shaft 201 carries a worm gear 210 which engages with a worm 211 onthe shaft 212, said shaft 212 carrying also the two pulleys 213, and214, said pulley 213 being fast on the shaft and the loose on the shaft.A belt (not shown) connected with suitable driving mechanism may beshifted from the loose pulley to the tight pulley to start the machine.Shaft 189 carries a bevel gear 216 which engages with a bevel gear 217on driving shaft 201, and also carries bevel gears 197, 218 and 219which engage with bevel gears on the carrier rolls 38, 381 and 382.

pulley 214 being The lower welding rolls,'391, are driven by the shaft201 through the following mechanism. Mounted on the shaft 201 is a spurgear 220 which engages with the spur gear 221 on a stud 222. Mounted onthe hub of said gear 221 is a sprocket wheel which carries the otherwelding roll 391 carries a sprocket wheel 230 which is connected byachain 227 with a sprocketwheel 47, and the shaft 47, as already j by awire 147 with the brushes 82.

on shaft described is driven by the shaft 121. The

' said second shaft 122 and the second Welding roll 391 will thus bedriven.

The upper strip welding rolls 39, 39 are driven by gear connection ofthe shafts 101 and 101 with the shafts 122, and 122 respectively, asfollows: Mounted on each of the shafts 122 is a spur gear 228 whichengages with the spur gear 229 on the shaft 101, the spur gear 228 beingmade of fiber or other insulating material so as to prevent electricalconnection between the two gears. The gear 228 on one of the shafts122engages with a gear 230 which in turnengages with a train of gears231, 232 and 233 to actuate the car-"ier rolls which carry off thewelded plates after they have passed the strip welding rolls. Each ofthe car-. rier rolls 30, 38, 381, and 382 is provided with beveledcollars 240, which form guides for the work as it passes through themachine. These collars are split and clampedto the rolls on which theyare mounted and may be adjusted to different distances apart from eachother according to the width desired. I 1

During theoperation of the spot welding roll the points'of the buttons34 will attach to themselves fine particles of metal from the plate withwhich they come in contact and thereby diminish the conductivity. Forthis reason there is provided means for brushing the .points of thebuttons 34 during each rotation. The means provided are as follows: Aroll '97 of emery or other suitable abrasive material is journaledalongside of the welding roll sufficiently close to the spot weldingroll to grind the points 34 of the spot welding 'roll at each rotation.The shaft of the grinding roll carries a pulley 98 which is connectedwith suitable driving mechanism to rotate the grinding roll in oppositedirection. to the rotation of the welding roll. in order to'allow forthe gradual wearing away of the grinding roll and of the points 34 thebearings of the grinding roll shaft are made adjustable so that thegrinding roll may be movedtoward the welding roll as occasion requires.

In the diagram of the Wiring for the spot welding roll shown in Fig. 12one wire of-each primary is connected with a'wire 142 leading to thecontact 90. The other v wire of each primary is connected with the wire143 leading to one pole 144 of a switch 148, and the wire 92 which leadsfrom the contact 91 connects with the other pole 145 of the switch; Bymeans of the switch which is connected with the enerator the current maybe turned on or 0 at any time. One end ofeach secondary coil isconnected 'vided with a head 254' and other end of each secondary coilis connected In the diagram of the wiring connected with the stripwelding rolls, as shown in Fig. 13, one wire of each primary 150 isconnected with a wire 170 leading to the contact 164 and the other wireof each primary is connected with the wire 171 leading to one of thepoles 172 of the switch 173 connected with the generator, and the wire.166 which leads from the contact 165 is connected with the other pole173 of the switch 174. One end of each secondary coil-152 is connectedbye wire 175 with the tail piece 157 which is con nected with the stripwelding roll 39, and the-tother end of' each of said secondary coils isconnected by a wire 176 with the tail piece 156 of the lower. stri'owelding rolls 391.

'During the operation of the strip welding rolls 39, 391 fine particlesof metal from the plate with which they come in contact will attachthemselves to the said rolls and therebydiminish the conductivity of thesaid rolls in the same manner as described with reference to the spotwelding rolls. For this reason it is important to provide means for- 243which extends toward the strip welding rolls. v in which ismounted ashaft 245 which carries a grinding or abrading wheel 246 which as willbe hereinafter explained is' adapted to be moved into position to beengaged by the strip welding rolls during their rotation to grind offthe particles which may .be attached to the strip Welding rolls. Theshaft 245 and therefore the grinding roll 246 may be rotated by anysuitable driving mechanism, the means shown in the drawings being anelectric motor 247 which carries on its shaft a pulley'248 which isconnected by a belt 250 with a pulley 249 on the shaft 245. The guidebar 241 rests on the frame 251. Adjusting screws 252 pass transverselythrough the said guide bar 241 near each end, the inner end of each ofsaid adjustingscrews passing through a fixed bracket 253, said adjustingscrews being each proa collar 255, said head and collar bearing againstopposite sides of the bracket 254 so that the" adjusting screw isprevented from longitudinal Said arm 243 carries a bearing 244 hole inthe guide bar 2 11 through which the :uljusting screw passes is tappedout so that by turning the adjusting screws the guide bar will be movednear enough to the strip welding rolls so that by then sliding thecarrier on the guide bar to bring'the grinding roll into alinement withthe welding roll, it will engage the welding roll. Preferably thegrinding apparatus is so located that the grinding roll will at the sametime engage with one of the upper strip welding rolls 39 and with one-ofthe lower strip welding rolls 391. The grinding roll is mademovabletransversely of the machine so that it may be brought into engagementwith the strip welding rolls of one section at onetime and then movedover to the other side of the machine to engage with the strip weldingrolls of the other section and also to enable the grinding roll to bemoved to one side to permit the passage of the plates to be weldedbetween the welding rolls. WVhen the bar 241 is adjusted it will beclamped in the adjusted position by means of a clamp screw 256.

The operation of'the machine'is as follows,lf the two plates are to bespot welded-together, as for instance the fiat plate 2 and. thecorrugated plate 3, as previously described, the two said plates beingproperly assembled in the manner previously described in the grid, asshown in Figs. 7 and 8, the grid will be placed upon the rolls 30properly positioned between the guide collars 240 and advanced until theplates are gripped between the feed roll 31 and the presser roll 32, andas soon as gripped by said feed and presser rolls the assembled partswill he carried between the spot welding roll and the platen and will befed through. When one of the buttons 34 of the spot welding-roll comesin contact with the flat plate 2 the electrical circuit will be closedin the manner-already described and the two plates will be united by awelding spot. As the plates continue to feed forward they'will be weldedtogether in as many spots as the number of times that they come inengagement with one of the buttons. As soon as the plates pass throughsufficiently far to come into engagement with the second feed roll 36they will be gripped between said feed roll and the presser roll 37 soas to insure that the feed will be continued after the work 'passes frombetween the feed roll 31 and presser roll 32. It will pass from the feedroll 36 out on to the carrier roll 38' and thence onward but it will beremoved before it is engaged by the feed rolls which lead to the stripQ'welding rolls or the strip welding rolls may be raised out of contactwith the panel, or the current may be cut ofi so that if the plates areallowed to continueon through the strip welding rolls there willrbe nowelding by the strip rolls. Then the two parts which have thus beenwelded together will be assembled with the plate'l and the hinge platesin the jig as previously described, being now turned up side down sothat the fiat plate 1 instead of plate 2 will come on top, and it willbe drawn through over the platen and beneath the spot welding roll, thuswelding together the plate 1 and the corrugated plate 3. This time thethree plates thus welded together carrying the hinge plates assembledwith them will be allowed to be-carried forward between the stripwelding rolls, and the two hinge members on opposite edges of theassembled plates will be welded to both plates 1 and 2, the plate 2being Welded to one leg of the hinge plate and the plate 1 being weldedto the other leg of the hinge plate by a continuous line'of weldingparallel with the edge.

What I claim is:

1. In an electric welding machine, a r0 tary welding roll having aplurality ofelec- I trio contact points projecting therefrom, in

combination with a platen of conducting material mounted in relation tothe welding roll in such manner that when the material to be welded ispassed between the welding roll and the platen it will be engaged bythe. contact points on said welding roll and feed rolls whichautomatically feed the work into and out from between the welding rolland the platen.

2. In an electric welding machine, a rotary welding roll having aplurality of contact points projecting therefrom, in combination with aplaten of conducting material mounted in relation to the welding roll insuch manner that when the material to be welded is passed between thewelding roll and the platen it will be engaged by the contact points onsaid welding roll, feed rolls which automatically feed the work into andout from between the welding roll and the platen, and means for drivingsaid feed rolls and said welding roll at the same surface rate of speed.

3. In an electric welding machine, a rotary welding roll having aplurality of contact points projecting therefrom, said welding rollcomprising a plurality of c linders of, conducting material concentricwith each other, and insulating material separating electrically saidsections from each other, all of said sections being united togetherinto one rigid roll. H A

4. In an electric welding machine, a 1'0- tary welding roll having inits periphery a plurality of contact po nts, said welding rollcomprising a plurality of cylinders of conducting material concentricwith each other, insulating material separating electrically saidsections from each other all of said sections being united together intoone rigid roll, in combination with a platen composed of a plurality ofsections of condUcting material corresponding with the several sectionsof the said welding roll, insulating material separating electricallythe 'said several sections of the platen, said platen being so locatedwith relation to the welding roll that when a plurality of plates ofconducting material superposed upon each other are passed between saidwelding roll and said vplaten, one of said plates will be engaged by thecontact points on said welding roll and another of said plateswvill bewelded together are passed between the welding roll and the platen oneofthe articles will be engaged by the "contact points on said weldingroll, said contact points bea ing so disposed on said welding roll thateach one of said contact points makes welding contact with the work andthen passes out of welding contact before another one I of said contactpoints comes into welding contact with the work, but in passing 05 fromthe work said first contact point continues in suilicient contact toafford a conto afford an outlet for the current until the tinuous outletfor the current until the said next succeeding contact point comes intocontact with the work sufiiciently to carry the-current but notsuiiiciently to make simultaneous welding contact. r

6. In an electric'welding machine, a rotary welding roll having aplurality of contact points projecting therefrom, said contact pointsbeing so disposed on said.welding roll that, each one of said contactpoints makes welding contact with the work and then passes out ofwelding contact before another one of said contact points comes intowelding contact with the work, but in passing off from the work saidfirst contact point continues in sufiicient contact to afford acontinuous outlet for the current until the said next succeeding contactpoint comes into contact with the work sufficiently to carry the currentbut not sufficiently to make simultaneous welding contact.

7. In an electric welding machine, a rotary welding rollhaving in itsperiphery a plurality of contact points disposed, in such manner-thatonly one of the said" contact points will be in welding contact with thematerial at any one time, and that each con tact point will graduallyrelease its pressure and contact, remaining in sufiicient contact cuit.

welding roll rotates far enough for another contact point to take up thecontact.

8. In an electric Welding machine, a rotary welding roll having in itsperiphery a plurality of contact points, a support of conductingmaterial for the Work which is welding roll the Work is passed and somounted in relation to the welding roll that when the work is fed alongon thesaid support and said Welding roll is rotated said contact pointson the welding roll will suecessively engage the Work and close thecircuit, 'in combination with a rotary strip Welding roll having acontinuous ring of conducting material around its periphery,

a support for the materials to be welded together located beneath saidwelding roll,

said support being composed of electric con-' tary Welding roll havingin its periphery aplurality of contact points, a lever having hearingsin which saidwelding roll is journaled, and a shaft on which said yokelever is fulcrumed, and on which said yoke lever may be rocked to raiseor lower said welding rolL- 10. In an electric welding machine, a rotarywelding roll having a plurality of con- 'to' be welded and between whichand the tact points projecting therefrom, a yoke lever having bearingsin which said welding roll is journaled, a shaft on which said yokelever is fulcrumed, and on which said yoke lev'er may be rocked to raiseor lower said welding roll, in combination with a support for thearticles which are to be welded together, said support being made ofconducting material, and located beneath said welding roll and adjacentthereto so that when the articles to be welded together are superposedupon each other and fed across, said support beneath the'welding roll,one

of said articles will be successively engaged by said contact points onthe welding roll, and the other of said articles will be in contact withsaid support, in combination with a source of electric energv having onepole connected with said'welding roll and hav- ,ing the otherpoleconnected with said su'p-' port whereby'the succgssive contacts ofsaidpoints on the welding roll with said mate rial will make successiveclosures ofthe cir- Ini'itn electric welding machine, a support ofconducting material for the articles to be welded, a rotary welding rollabove said support and adjacent thereto, having ort a make and breakdevice in the circuit having two contact members normally separated fromeach other, one of said contact members being connected with saidrocking mount, and being actuated by the rocking of the mount when thework passes between the roll and said work support to close the circuit.

12. -In an electric welding machine, a sup- I port of conductingmaterial for the work which is to be welded, a rotary welding rolladjacent to said support and having conducting material therein, amovable mount for said welding roll which together with the welding rollis raised and lowered by the passing between the said welding roll andwork support of work of greater thick ness than the space betweensaidwelding roll and work support, an electric circuit which includessaid welding roll and work support, a make and break device in saidcircuit having two contact members normally out of contact with eachother, one of which is connected with and actuated by the said movablemount forthe welding roll during the passingof work between the saidwork support and said welding roll to make the contact with said othercontact member, the said roll and work support alsobeing electricallyconnected by said work contacting with both said roll and support,thereby clos ng the circuit.

13. In an electric welding machine, mechanism for welding togetherelectrically two metal plates at different spots, mechanism for weldingtogether electrically two metal plates along a strip line, and means forautomatically feeding the said metal plates through one of said weldingmechanisms, and thence to and through the other of said weldingmechanism.

14. In an electric welding machine, mechanism for welding togetherelectrically two 7 metal plates at diliere'nt spots, mechanism forwelding together electrically two metal plates along a strip line, aholder for a plu- 'rality of plates which holds them in proper relationto each other for welding, and meansfor automatically feeding the holderwith said plates through one of said welding *-mechanisms and thence toand through the other of said 'welding'mechanisms. k

15. In an electric welding machine, a rotary welding roll havingconducting material thereon, a'movable mount for-said roll, a worksupport beneath said welding roll and adjacent thereto, havingconductingmaterial therein, a source of electric energy, an electric circuit withwhich said welding roll and work are-each connected electrically, saidroll and work support being normally separated from each other, twocontact points in the circuit normally separated from each other,thereby making a break in the circuit, a lever connection be tween oneof said contact points and said roll, said roll being elevated by thepassing of work between'the roll and said work support of greaterthickness'than the normal space between said roll and support andthereby actuating the said lever to cause said movable contact toengage'the other contact and close the circuit.

16. In an electric welding machine, a rotary welding roll having aplurality of electric contact points in the periphery thereof, anelectric'circuit which is normally open and with whichsaid contactpoints are electrically connected, a work support over which thematerial to be welded is passed, and which is within said electriccircuit, a make and break device within said circuit, and means wherebythe introduction of conducting material be-' tween said Work support andsaid welding roll will close the circuit each time. that one of saidcontact points engages with said introduced conducting material. v

17. In an electric welding machine, a rotary welding roll having in itsperiphery contact pointsdisposed in staggered relation to each other.

18. In an electric welding machine, a rotary welding roll havingconducting mate-' rial in its periphery, a support for the articles tobe Welded, said support being made of conducting material and locatedbeneath said welding roll and adjacent thereto so that when the articlesto be welded together are fed across said support beneath the weldingroll the uppermost of said articles will be engaged by said welding rolland the lowermost of said articles will be in contact with said support,a source of electric energv having one pole connected with said Weldingroll and the other pole connected with said support whereby the contactof said articles to be welded with said support and with said weldingroll will close the circuit, in combination with a holder having meanswherebysaid articles to be weldedtogether are retained in theirassembled form during the passage of said articles through the weldingmachine.

19. In an electric welding machine, a rotary welding roll having'in itsperiphery a

